Oops, it doesn't look like 'strike may day' is a national day..

Other days

comfy

Comfy Day
cuddle up

Cuddle Up Day
boy friend

Boy Friend Day
bow tie

Bow Tie Day
my little pony

My Little Pony Day
hoodie

Hoodie Day
ruby

Ruby Day
one

One Day
prosecco

Prosecco Day
special education

Special Education Day